Audi Accessory Drive Belt Idler Pulley - Genuine Audi 079903389D

Product Information

The drive belt idler pulley works in conjunction with the tensioner pulley/tensioner assembly to maintain tension on the belt as well as guide the belt. Idler pulleys are also used to achieve ideal belt routing around the engine drive accessories such as the power steering pump, water pump, A/C compressor, and alternator.

The idler pulley is an often overlooked maintenance item but it is just as important as the belt tensioner itself. In most cases it is recommended to replace the idler pulley at the same time as the belt tensioner.

• Visible wear or grooves on pulley
• Belt squealing
• Chirping or grinding sounds coming from pulley bearing
• Odd or uneven belt wear
• Misalignment of pulley when compared to mounting surface

About Genuine Audi

The original parts used by Audi to build your car are available as replacement parts under the “Genuine Audi” brand. Manufactured under the direction of Audi, expect excellent quality and a premium price since these parts are available exclusively through the Audi Dealership network.

You may not realize this, but the parts that make up your Audi are not necessarily manufactured by Audi. No cause for concern, as Audi designs the part, hires a manufacturer, and ensures its quality to you. In fact, many of these manufacturers have been making parts for Audi for decades. In our industry these manufacturers are called OEM (Original Equipment Manufacturers), and these are often brands you recognize, including Lemforder, ZF, Sachs, Bosch, Valeo, Zimmermann, Siemens VDO, Corteco, and more. Don’t be surprised to open that Genuine Audi parts box and find an OEM branded part inside, simply with the addition of an Audi logo.

Be sure to keep an eye out for OE tags on our product pages to quickly identify parts coming direct from OE manufacturers. That extra bit of insight could save you some serious money while shopping! Refer to our OE Academy for further information regarding the OE/OEM tags throughout the site.